i think weed may make you more anti social, if you have those tendencies to begin with. if you're a very social, outgoing person, i don't think it'll turn you into a hermit.
likewise with the aggression, if you're a very peaceful, non violent person, i don't think getting high is going to make you go look for a fight. if you're already an asshole, it might make you a bigger asshole, or it might mellow you out, i'd say it depends very much on whats going on around you at the time. it sort of amplifies normal things, so if theres a lot of annoyances at the moment, they might get amplified to the point where you have to do something about it. that makes you look a little crazy to those who aren't being annoyed by the same things you are.